The invention relates to mechanical fasteners, particularly for mounting electronic components to printed circuit boards.
It is often necessary to mechanically mount components to a printed circuit board. For example, a second, smaller xe2x80x9cdaughterxe2x80x9d board may be mounted to a larger xe2x80x9cmotherxe2x80x9d board, parallel to and adjacent to the board. Similarly, components such as integrated circuit chips, and connectors having planar portions to be connected to a mother board are connected with a main portion in parallel with the board. Such components may have an array of pins that extend to electrical contact with a receptacle on the board, providing electrical connection.
Attached components often must be mechanically secured to the mother board. In many instances, conventional fasteners may be used, such as by passing a screw through holes in each board. However, many such fasteners require access to the opposite side of the mother board for installation. Other fasteners, such as those using a snap mechanism that connects to the mother board permit such xe2x80x9cblindxe2x80x9d attachment (when the opposite side is inaccessible,) but do not permit repeated extraction and firm reconnection, as is often required for testing, and for service of certain components.
Conventional fasteners may also be difficult to use. Even where fasteners are provided readily on a mother board to accept a daughter board, these are often difficult to align with holes on the daughter board, because the daughter board obscures the fasteners as installation is attempted. This risks misalignment, damage to mating connector pins, and unwanted contact of components on either board as alignment is being sought.
The embodiments disclosed herein overcome these limitations by providing a facility for mounting an electronic component includes a first circuit board having of mounting apertures. A mounting element is associated with each aperture, and includes a boss defining a bore. The boss has a first surface contacting a major surface of the first circuit board, and a second surface opposite the first surface. A pin is received in the bore, and has a lower portion protruding from the first surface of the boss and into one of the apertures. The pin""s lower portion defines a space to capture a portion of the first circuit board. A fastener connected to the pin may generate compression between the space and the boss to secure the board, and a corner-shaped protrusion on the second surface may constrain the corner periphery of a second board resting on the second surface, with the fastener also securing the second board against the boss.